Why You Should Groundtruth Yield Maps

Using yield maps, farmers can build a foundation for variable-rate nitrogen application, Farm Journal field agronomist Ken Ferrie says in Episode 11 of Corn College TV Season 3.

To illustrate that reality, Ferrie shows two corn plants growing in different field management zones.

"As we look at this plant, even though it’s got the same rate of nitrogen, we see nitrogen drawdown down here at the base," Ferrie says. "We start with nitrogen at the tip, moving down the mid-rib of that leaf. This plant is cannibalizing itself at a pretty heavy pace, while its counterpart in the other parts of the field that are in good shape still has these bottom leaves on and there’s no firing within it."